Abnormal "activated" rosette formation in patients with gastrointestinal cancer

The mean percentage of peripheral blood lymphocytes forming fast spontaneous rosettes with sheep red blood cells was estimated in 40 patients presenting with gastrointestinal symptoms suggestive of cancer. Patients who were eventually diagnosed as having cancer had significantly lower numbers (P less than 0.01 Mann Whitney Test) of rosette forming cells than patients who had gastrointestinal tumours successfully removed, or patients with other gastrointestinal diseases. The use of this test as an aid to the diagnosis of gastrointestinal malignancy and its possible application to the detection of recurrences of cancer after surgery are discussed.